Build in WSAD 5.1.1, but deploy to WAS 4.0 and use Struts. - Websphere

This is a discussion on Build in WSAD 5.1.1, but deploy to WAS 4.0 and use Struts. - Websphere ; Hi!
Our development environment is WebSphere Studio V5.1.1 but we have to
deploy to WebSphere Application Server 4.0
What would be a good source of issues(what is supported or not) about
building the application in WSAD 5.x (5.1.1) and deploying ...